Zinsser 123 causing paint problem

[SJRSJR]

We recently had a damp problem and found the wall cavity had been bridged by building rubble, which we sorted. We ended up hacking off all the old plaster and had the wall completely replastered. The area where it has been damp took much longer to dry out but when it was finally ready to paint I first did a mist coat with white matt emulsion, except in the area where the damp patch had been, I thought I was doing the right thing by using Zinsser 123 on it, just in case any staining came through the new plaster. Now I've started painting with a Dulux Diamond Matt colour and there's a discrepancy where the Zinsser is. I'm on the third coat but it doesn't seem to be getting any better.

Have I done a stupid thing or should I persevere with the coats? Thanks

 

[footprints]

Just keep coating, Zinsser dries to a sheen and may show through because the texture is different to the surrounding even more pronounced if you used a brush for the Zinsser and roller for the rest.
You need to build up the texture of the paint finish that's all

 

[SJRSJR]

Thanks very much. I painted it on but I put the damp roller I used for the mist coat over it to try to even out the texture. Will keep going!